I have a Project with a namespaced npm-repository. Which means that an @ appears in the directory-name: @xstable/gatsby-theme-onepager.
The Gitlab-UI (not selfhosted) has a bug with handling this.
If I click at the Repository-Name it replace the @ with an url encoded %40:
If I replace the %40 in the adress-bar of the browser, the directory will be shown in the right way.
Same on Web-IDE.